Conserving Water in Your Garden – How to Grow Australian and Other Dry Climate Plants

Conserving water is obligatory for gardeners in Mediterranean and other dry climates. For this purpose, a number of plants are suggested by nurseries and in garden literature that can be grown on very little or even no additional irrigation through the year. Many of these drought-resistant plants, known as xerophytes, are of immense value as landscape, garden ornamentals. Many originate from the dry regions of Australia.

Unfortunately, professional and home gardeners are aware of the relatively high failure rate amongst Australian plants, and as a result, species and varieties of Grevillea, Melaleuca, Eremophila, and Myoporum, to give a few examples, are loosing their appeal. This is a great pity, as a large number of trees, landscape shrubs and sprawling ground covers belonging to these genera are both beautiful and functional garden plants.

However, a better understanding of the growing requirements of these plants should result in reducing the mortality rate to the point that a small amount of failure is both acceptable and tolerable. The essence of the problem is that gardeners tend to care for them in the same way as sub-tropical species such as Citrus trees, or herbaceous perennials and even annuals.

A maintenance regime based on frequent watering and generous feeding may be suitable for most garden plants, but not for many drought resistant ones from Mediterranean climates, and especially for Australian ones. What in short should you be doing to give your Grevillea, Hakea, and Banksia e.t.c. bushes a better chance of surviving and thriving?

Good Drainage

Xerophytes are far more sensitive to a lack of air in the soil, than a shortage of moisture, so good drainage is the prerequisite for avoiding disappointment. Some plants, such as Banksias need perfect drainage, but few or none can tolerate anything resembling boggy conditions.

Minimal Feeding

Almost all species from the Proteaceae family, to which many Australian and South African xerophytes belong, are highly sensitive to excessive levels of salt and fertilizers in the soil, and especially to phosphorous. While compost improves the soil’s porosity, excessive quantities are liable to release too much mineral nutrient in the root zone. Similarly, Junipers, which are largely of Asian and Mediterranean origin, suffer from high doses of nitrogen fertilizer. Their nutritional needs can be more than catered for by compost or worm castings.

Patience

Species of Melaleuca, Myoporum, Grevillea, e.t.c. have to be allowed to grow at their own pace, and not forced by frequent irrigation and fertilizing to grow rapidly. In fact, this often causes plants to suddenly collapse after a year or so. Watering should be kept as low as possible just to ensure the young plants’ survival, and not in order to force them to cover space quickly. It follows therefore that as well as specific irrigation, soil, and feeding requirements, many of the excellent garden plants that are ideally suited to dry climates, need a good dose of patience from those in their care!